Onion

Name: Onion (Allium cepa), the common bulb onion, grown in many types and colours, including yellow, white and red. More specific kinds, such as shallots, spring onions and sweet onions, have their own pages.

Description

The onion is thought to have been first domesticated in central Asia thousands of years ago, and was a staple in ancient Egypt, Greece and Rome, where it was valued as food and medicine. It is now one of the most widely grown vegetables in the world, with India and China as the largest producers.

Onions make people cry because cutting them breaks open cells and releases a gas called lachrymatory factor that irritates the eyes. Cooking changes onion's taste dramatically: raw it is sharp and pungent, while slow cooking turns the natural sugars sweet and golden, as in French onion soup.

Main nutrition value

Onions provide vitamin C, vitamin B6, folate and potassium, along with the plant antioxidant quercetin and prebiotic fibre, though they are usually eaten in small amounts.

How best to be consumed

Onions are the base of countless dishes, raw and cooked.

1. Fry gently as the base for soups, stews, curries and sauces.
2. Caramelise slowly over low heat for sweet, golden onions.
3. Slice thinly raw into salads and sandwiches, soaking in cold water to mellow the bite.
4. Roast or grill thick slices or whole onions.
5. Chill the onion before cutting, or cut under a fan, to reduce tears, and store in a cool, dry, dark place.

Overconsumption could cause…

Onions are safe in food amounts for people, but toxic to pets.

1. Bloating, gas or heartburn, since alliums contain fermentable carbohydrates (fructans) that bother many people with IBS.
2. Heartburn or reflux in some people, particularly after raw onion.
3. Allergic reactions or skin irritation in a small number of people sensitive to alliums.
4. Poisoning of dogs and cats, for whom onions are toxic.

GroupsAllium VegetablesAllium (onion family)Low fatLow sodiumFresh

Related foodsYellow OnionRed OnionWhite OnionWelsh OnionSpring Onion / ScallionSweet Onion

Wikipedia — Onion, used for origin, naming and history: https://en.wikipedia.org/wiki/Onion